A fin type transistor having a fin structure is known as one of the double gate type transistors each having a channel region held between two gate electrodes in order to enhance controllability for a current by the gate electrode. The fin type transistor has a property which has an advantage to enhance miniaturization of an device, cut-off characteristics and a carrier mobility, and to suppress a short channel effect.
A Static Random Access Memory (SRAM) using fin type transistors is known as a conventional semiconductor device. The SRAM using the fin type transistors, for example, is described in WO 05/036651 (pamphlet).